Chain grate stoker



Jan. 29, 1929. 1,700,707

J. w. PECK CHAIN GRATE S TOKER Filed July 9, 1925 WITNESSES INVENTOR WM Jess IMPeck A BY w W I L 1mm I ATTQR Y Patented Jan. 29, 1929.

UNITED STATES JESS W. PECK, OF NEW YORK, N. Y., ASSIGNOR TO RILEY STOKER ATENTYOFFICE.

CORPORATION, OF

WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

CHAIN GRATE s'roxnn.

Application filed July 9, 1925. Serial No. 42,420.

This invention relates to chain grate stokers and more articularly to the clip or grate bar which is astened to the chain and adapted to support the fuel bed of the type shown in the patents to Harrington, Nos. 1,326,590 and 1,326,591 of December 80, 1919.

In such stokers an endless chain is used to feed fuel into the furnace combustion chamber. In this construction, two parallel chains are connected by cross bars and slidably mounted on these cross bars are a plurality of clips or specially shaped blocks adapted to serve as grates and tuyeres. These clips or grate blocks are so formed and shaped that they form a substantially continuous flat surfaced fuel supporting bed and permit air to enter the fuel through tuyere passages between the individual clips.

It has been found that the grate blocks of this general type as heretofore used have certain defects which prevent an efficient operation of the furnace. Because of the peculiar shape of the block, there is a tendency for the heat of the fuel bed to burn oif the ends of the block and render it necessary to shut down the stoker at fre uent intervals for repairs. Also large clin ered masses tend to accumulate at the centers of the blocks thereby causing the fuel to burn unevenly.

It is accordingly the main object of my invention to overcome these difiiculties and to provide a grate block or clip for a chain grate stoker whlch will give a long life of service and be highly eflicient in itsoperation and which wil cause an even distribution of air tothe fuel and will not permit an accumulation of unburned or clinkered material to remain on the block.

With this and other objects in view as will be apparent to one skilled in the art, my inventlon resides in the combination of parts set forth in the specification and covered by the claim appended hereto.

Referring to the drawings, in which like reference numerals indicate like parts:

Fig. 1 is a to plan viewof a portion of a chain grate sur ace;

l Fig. 2 is a top plan view of one of the grate c 1 si. a is a side elevation of the clip;

Fig. 4 is an end elevation; and

Fig; 5 is a cross sectional view on the line 5-5 of Fi 1. w

In accor lace with my invention, I propose to so shape and construct the clip that its top surface which supports. the fuel bed will be narrow and have substantially the same width throughout its entire length, and will not have a wide fuel supporting surface at its medial portion but is so formed that fuel can a not accumulate in'an unburned or clinkered condition anywhere thereon. The clip is shaped to form'a central top portion having arms extending parallel with each other but offset in a somewhat zig-zag fashion, which is so arranged relative to the other clips that the forward end of one clip interfits between the two rear ends of the clips mounted in an adjacent row.

The particular clip illustrated in' the draw- 7 ings comprises a metal body having a substantially flatJtop surface 10 shaped as two long rectangles of uniform width joined in an offset manner, to a medial portion. Each clip has an arm composed of a vertical web 7 11 and a fuel supporting flange18, and a second arm composed of a vertical web 11', a fuel supporting portion 15, and a horizontal flange 16. An enlarged slotted portion 12 is located centrally of the clip and is provided 8 with a groove 13 adapted to he slid over a below the top surface 10 by a distance slightcorrespondingly shaped bar mounted on the ly greater than the thickness of the flange 18 on the other arm of the clip. These two flanges 16 and 18 are therefore offset relative tolleach other both vertically and horizonta y.

It will be seen by reference toFigs. 1 and 5 that the clips are interfitted in such a way that the fuelsupporting flanges 18 lapover the projecting flanges 16 and are spaced therefrom slightly in a vertical direction and that the flanges 16 are spaced somewhat hori- 1 zontally, fromthe vertical webs 11 in order to provide for the circulation of air between the blocks. I also may provide spaced grooves or channels 19 in the sides of one of the arms, such as the portion 15,'to serve as 1 tuyere openings and insure the passage of air upwardly through the tortuous channel between adjacent clips. These clips are so mounted. on their support as shown in the patent to Harrington 1 o N 0. 1,326,590 that as the clip reaches the end of its horizontal travel and turns downwardly the rear end of the clip will draw away from the front end of the adjacent clips' face which supports the fuel bed is substantially uniform throughout and that the central fuel supporting portion 20 is of about the same Width lengthwise of the clip as is the transverse w'idth'of the portion 15 and flange 18. This insures air being admitted 1 through tuyere openings which are substantially the same distances apart, and air is admitted through the spaces 21 very close tothe center of the top of the clip. The arms of the clip are made of the same width and substantial in size so that they will not burn I away readily and if they do burn to some extent there is considerable metal in the webs and other adjacent portions which will carry the fuel bed and prevent a large volume of air escaping upwardly into the fire,

or any considerable amount of fuel falling past the burned ofl portion of the clip.

Having thus described my invention, What I claim as new and desire to secure by Letters Patent is:

A grate block for a chain grate stoker comprising a unitary casting having a vertiother block and form a tortuous passage therebetween, when the parts are normally assembled, the top of the block being shaped to form two laterally oifset arms having parallel side's and a top surface of substantially the same width throughout and these arms having small uniformly spaced vertical grooves on a side thereof which are arranged to conduct air from beneath the block to a fuel bed supported thereon.

Signed at New York, N. Y., this third day of July, 1925.

v I J'ESS Wl PECK. 

